Continuity mistake: Columbo stops Mr. Finch on the road after following him from Biltmore hotel; as Columbo is speaking with him, the cigar in Columbo's hand is always in Finch's shot, even after we see Columbo place his hand on the roof. Plus after we see him put his hand down, the cigar ash keeps going from 1" to nothing. (01:44:20)
Butterfly in Shades of Grey - S12-E2
Other mistake: Fielding Chase and Lieutenant Columbo are on a road in the mountains above Malibu and Chase's car will not start. He tries unsuccessfully to call the Automobile Club on his mobile phone. He tells Columbo the phone number is "555-4411" but each time he tries to call, he presses nine digits.
Butterfly in Shades of Grey - S12-E2
Continuity mistake: From his estate, Fielding Chase looks toward his front gate and sees smoke coming from the engine of Columbo's car. When we see Columbo standing atop the car and yelling for Chase to open the gate, there is no smoke.
Character mistake: Tommy Brown (Johnny Cash) broke his left leg. Throughout the show, he uses his crutch and then his cane on the left side. It should be on the right (opposite) side.
Factual error: Santini murders Jerome using a revolver with a silencer. Although this is one of the oldest Hollywood tropes, a silencer (properly called a suppressor) does not reduce a gunshot to a whisper; it only cuts the noise to about 110 dB, which is still very loud. In addition, suppressors do not work at all on revolvers, because most of the noise is generated in the gap between the cylinder and the barrel.
Factual error: All LAPD officers must re-qualify with their weapons multiple times a year. If indeed Columbo could not "hit the target," as he says to another detective, he would never have made it through the police academy, much less have become a detective and have been promoted to sergeant and eventually to lieutenant.
Other mistake: When Columbo is examining the crashed Jaguar, we see silvery tape around the opening where the smashed headlight had been. The tape shouldn't be there.
Short Fuse - S1-E7
Plot hole: We are told several times that the road to the mountain house is very narrow and difficult to negotiate. How did the very large crane get there so quickly to lift the bodies after the crash?
Undercover - S12-E3
Continuity mistake: When Krutch speaks to Columbo on the phone about 40 minutes into the show, his voice sounds like he has a cold. Earlier and later in the show, his voice doesn't sound like that.
Character mistake: Columbo talks to the cardiologist. The doctor gives him information about his patient, Mr. Williamson. Columbo has no warrant, so the doctor is violating privilege. He wouldn't give that information to Columbo.
Dead Weight - S1-E4
Other mistake: Columbo goes into a diner and has a bowl of chili. The cook asks if he wants his coffee black. Later he asks if he wants cream and sugar in his coffee.
Other mistake: When Rosanna's body is brought to the ship's medical room, the doctor confirms that there are no bruises on the body, but she had been forcibly slapped in the face earlier that day by Mr Danzinger (Robert Vaughn). The slap was hard enough to knock her over therefore a bruise should be visible, even through make-up.
Plot hole: The cruise ship is sailing from LA to Mazatlan in Mexico. Looking at a map, the ship will hug the west coast on its journey therefore is never far away from land. The murder takes place on the first evening of the cruise only a few hours after setting sail by which time they won't be far from San Diego. Why didn't the captain order the ship into San Diego or another suitable harbour and let the police take over the investigation?
Other mistake: Over a public address system, Cahill tells his staff to quit working on their World War III scenarios until "after lunch." He immediately returns to his office and the wall clock shows the time as 4:30.
Continuity mistake: When Columbo meets Goldie for the first time she is having a massage. She then proceeds to dress by tying a dressing gown with a bow at the front. In the next shot the dressing gown is open with the tie at the back.
Butterfly in Shades of Grey - S12-E2
Other mistake: Jerry Winters' mantel clock chimes four times but the clock shows the time as 3:59.
Continuity mistake: Colombo is talking to Mr. Kingston in the building entry after the reading of the will. A girl with red and white striped sleeves walks out of the building. A minute later she walks out of the building again. (01:15:50)
Continuity mistake: Just before the end we see a slide of Columbo looking at the lamp, but in the next shot of Columbo the slide is reversed.
Answer: In the show, he was already a Lieutenant. A promotion would put him in the next rank up, which for the L.A.P.D. would be Captain. However, some of a Captain's duties would be overseeing other officers and ensuring they're compliant with policies, regulations, and standards. It would also most likely take him out of the field. This is something Columbo has no desire for as he rarely goes to police HQ's. Nor does he show interest in compliance and standards (for example, not going to his semi-annual evaluation at the firing range). However, he could still be assigned to a higher pay grade based on expertise, which is a form of promotion that does not include rank advancement. This would be going from Lieutenant I to Lieutenant II. I don't believe in the show it's ever started what his pay grade is. Although, in s02e01 (I believe) he mentions making $11K a year. Whether or not this was a true statement on his part, if you could find pay scale information for an LAPD Lieutenant in the 70's, it could give you an idea of his pay grade.
Bishop73