Smalkin graduated from McDonogh School and received a Bachelor of Arts degree from The Johns Hopkins University, Phi Beta Kappa.

[4] He later became a rated pilot and Lieutenant Colonel in the Civil Air Patrol and was awarded its Distinguished Service Medal.

Upon relinquishing command of the Defense Force, he was awarded the State of Maryland Distinguished Service Cross.

[citation needed] He practiced law in Monkton, Maryland briefly in 1976, before entering Federal judicial service.

[5][6] Two controversial cases stand out from the many that Judge Smalkin heard during his thirty years on the bench.

First was his 1987 decision which overturned the conviction of Marvin Mandel, who succeeded Spiro Agnew as Governor of Maryland, for mail fraud and racketeering.

In a later case (in 2015), the Supreme Court decided that the purchasers of license plates cannot assert free speech rights with regard to their content.