He was a past President of the Genetics Society of America, and led a research team focused on the molecular mechanisms that regulate chromosome behavior during meiosis.

After finishing his PhD in 1979, Hawley secured a Helen Hay Whitney Postdoctoral Fellowship to study with Kenneth Tartof at the Institute for Cancer Research in Philadelphia, Pennsylvania.

Hawley's was appointed in 1982 as an assistant professor in the Departments of Genetics and Molecular Biology at the Albert Einstein College of Medicine in New York.

[1] Using the model organism Drosophila melanogaster, Hawley's research was focused on understanding how homologous chromosomes recognize one another, pair, and ultimately segregate from one another during meiosis – the cell division that produces sperm or eggs.

His work sought to gain a deeper mechanistic understanding of the synaptonemal complex (SC), a larger protein structure that assembles between the chromosomes during meiosis Hawley trained over 45 postdoctoral associates and graduate students.