Peter Sellers, Richard Attenborough
 
https://www.imdb.com/title/tt0055916/

The Dock Brief (US title Trial and Error) is a 1962 black-and-white British legal satire directed by James Hill, starring Peter Sellers and Richard Attenborough, and based on the play of the same name written by John Mortimer (creator of Horace Rumpole).
Richard Attenborough was nominated for the 1963 BAFTA Award for best British Actor for his role.

After 40 years of undistinguished practice Wilfred Morgenhall (Sellers), a cynical and unsuccessful barrister, is overjoyed to be assigned a dock brief: the defence of an accused murderer.
His client Herbert Fowle (Attenborough), is a meek man who wants to plead guilty to murdering his wife. Through a series of courtroom scenes and flashbacks the lead-up to the crime unfolds, involving Fowle taking in a lodger (David Lodge), who takes a more-than-passing interest in Mrs. Fowle (Beryl Reid). Morgenhall, given an opportunity to shine for the first time in his life, insists on pleading his client "not guilty."
But the case does not go as planned: Morgenhall botches the pleadings and Fowle is found guilty. As Morgenhall drowns his sorrows in a pub, he learns that the Home Office has overruled the verdict: Fowle has been declared not guilty on the grounds that his defence was inadequate.

The film was released in the USA under the title "Trial and Error."

Format                           : AVI
File size                        : 1.07 GiB
Duration                         : 1h 15mn
Overall bit rate                 : 2 023 Kbps

Video

Codec ID                         : H264
Width                            : 656 pixels
Height                           : 432 pixels
Display aspect ratio             : 3:2
Frame rate                       : 25.000 fps
Bits/(Pixel*Frame)               : 0.253
 

Audio

Format                           : AC-3
Bit rate                         : 224 Kbps