Born in Knoxville, Tennessee, Kindness graduated from Glendale High School in Glendale, California, in 1947. Kindness received his bachelor of arts degree from the University of Maryland in 1951 and his bachelor of laws degree from George Washington University in 1953.

He was assistant counsel for paper company Champion International, in Hamilton, Ohio, from 1957 to 1973, and was elected to the city council of Hamilton in 1964, serving until 1969. He served as mayor of Hamilton from 1964 to 1967. He served in the Ohio House of Representatives from 1971 to 1974, when he was elected to Congress from Ohio's eighth congressional district, defeating Democrat T. Edward Strinko.

Kindness was re-elected five times: defeating Democrats John W. Griffin in 1976, Luella R. Schroeder in 1978, John W. Griffin again in 1980 and 1982, and John T. Francis in 1984.

In 1986, Kindness won the Republican nomination for the U.S. Senate, but he lost to incumbent John Glenn. After this loss, Kindness stayed in Washington, D.C., and worked as a lobbyist. When Donald "Buz" Lukens, who had replaced Kindness as the 8th district's representative, was caught in a sex scandal in 1989, Kindness attempted to win his old seat, opposing Lukens in the 1990 Republican primary.

He entered a Republican primary battle that included Lukens, Union Township trustee John Boehner and lesser-known candidates.

Early polls gave Kindness a 60-point lead over the relatively-obscure Boehner. But Boehner attacked Kindness's ethics, citing Kindness's votes for congressional pay raises and against limits on fees for speeches by congressmen. Boehner also depicted Kindness as a carpetbagger who had abandoned his district for Washington. Despite Kindness's outspending him 5-1, Boehner won the nomination with 49 percent of the vote. Kindness finished with 32 percent and Lukens with 17 percent.

Kindness died while on vacation in Exeter, England at the age of 74.